Disposable iontophoresis system and tympanic membrane pain inhibition method

ABSTRACT

Systems and methods for treating a patient having an ear canal and a target tissue function by positioning a fluid or a gel in the ear canal, the fluid or the gel comprising a therapeutic agent; retaining the fluid or the gel with a support structure, the support structure supporting an electrode and a battery; and applying the therapeutic agent from the fluid or the gel to the target tissue by energizing the electrode with an iontophoresis potential from the battery.

CROSS-REFERENCES TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional PatentApplication No. 60/912,902, filed Apr. 19, 2007, the teachings of whichare incorporated herein by reference.

BACKGROUND OF THE INVENTION

The present invention is generally related to medical devices andapparatus. In particular, the invention provides systems, methods,devices, and kits for treating a patient's ear. In one embodiment, theinvention provides a system and method for tympanotomy, tympanostomy, ormyringotomy with or without tympanostomy tube placement, and for otherprocedures requiring manipulation or penetration of the tympanicmembrane such as tympanocentesis.

Otitis media is among the most common diagnoses made by pediatricians. Amajority of children may have at least one episode of otitis media(“earache”) prior to their third birthday. Otitis media is often causedby an inability of the eustachian tube to drain fluid from the middleear. Otitis media is often treated with antibiotics.

A significant number of children exhibit recurrent episodes of otitismedia and/or otitis media with effusion. Treatment of these more severecases often involves the placement of a tympanostomy tube through thetympanic membrane so as to provide adequate drainage of the middle earand reduce the likelihood of future infections. Tympanostomy tubesprovide fluid communication between the middle and outer ear, andtypically fall out spontaneously within about a year of placement.Tympanostomy tube placement is among the most frequent surgicalprocedures performed in the pediatric population. It has been estimatedthat more than a million tympanostomy tubes may be placed each year,with typical patients being between about 18 months and 7 years of ageat the time of the procedure.

Tympanostomy tube placement is typically performed in an out-patientsurgery setting under general anesthesia. The external auditory canaland tympanic membrane are examined under microscopic visualizationthrough a hand-held conical shaped speculum. An incision or myringotomyis made in the tympanic membrane, typically using an elongate, smallprofile scalpel which the physician extends through the conicalspeculum. Fluid may be aspirated through the myringotomy, and atympanostomy tube is placed so as to extend through the tympanicmembrane.

A wide variety of tympanostomy tubes are commercially available, and astill wider variety of others tubes have been proposed. A number ofsystems have been proposed to both perform the myringotomy and deploythe tympanostomy tube with a single treatment assembly. In recent years,more complex and expensive systems have been proposed for diagnosis ortreatment of the tissues of the ear, including systems using laserenergy for forming a myringotomy, video systems for imaging of the earcanal, and the like. These various alternatives have, not surprisingly,been met with varying degrees of acceptance.

A standard tympanostomy tube placement procedure is both effective andquite safe. Nonetheless, further improvements would be desirable. Inparticular, there are both risks and costs associated with out-patientsurgical procedures performed under general anesthesia. For example, asignificant portion of the risk and cost of tympanostomy tube placementis associated with the administration of general anesthesia, i.e., theneed for an operating room, the presence of an anesthesiologist, andrelated recovery room time.

In light of the above, it would be desirable to provide improveddevices, systems, methods, and kits for treatment of the tissuestructures within the auditory canal. It would generally be beneficialif these improvements facilitated myringotomy with or withouttympanostomy tube placement without having to resort to generalanesthesia, thereby allowing these common procedures to be performed ina doctor's office (rather than in an outpatient surgical facility).There are some studies that suggest placing children under generalanesthesia may induce neurodegeneration in the developing brain.Therefore, it would be desirable to provide devices, systems, methodsand kits for treatment of the tissue structures within the auditorycanal without using general anesthesia. It would further be desirable ifthese improvements could be provided while decreasing the overallprocedure time, and ideally, at a reduced overall procedure cost.

BRIEF SUMMARY OF THE INVENTION

The present invention provides systems and methods for the provision ofpainless, simultaneous, bilateral treatment of the target tissues of theear of children suffering from recurrent otitis or otitis media witheffusion in an office-based procedure with awake, mobile patients,created to manage the child's anxiety.

In one aspect, the present invention provides systems and methods fortreating a patient having an ear canal and a target tissue that functionby positioning a fluid or gel in the ear canal, the fluid or gelcomprising a therapeutic agent; retaining the fluid or gel with asupport structure, the support structure supporting an electrode and abattery; and applying the agent from the fluid or gel to the targettissue by energizing the electrode with an iontophoresis potential fromthe battery.

In another aspect, the present invention provides systems and methodsfor the direct visualization and the targeting and range finding for thetarget tissue of the ear which facilitate the visual and/or opticalmonitoring and thus a more effective treatment of the target tissueregion. In one aspect, the present invention provides systems andmethods that enable a clinician to specify a range or distance or havemechanisms like visualization or markers that can locate or appreciatethe distance from the treatment device and the tympanic membrane.

Advantageously, such systems and methods facilitate performing treatmentprocedures such as myringotomy, tympanostomy tube placement,tympanocentisis and the like, under local (rather than general)anesthesia, often in a doctor's office (rather than an out-patientsurgical facility).

For a further understanding of the nature and advantages of theinvention, reference should be made to the following description takenin conjunction with the accompanying figures. It is to be expresslyunderstood, however, that each of the figures is provided for thepurpose of illustration and description only and is not intended as adefinition of the limits of the embodiments of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates the simplified support structure that is worn on thepatient's head.

FIG. 2 illustrates views of a simplified ear canal.

FIG. 3 illustrates the insertion of an exemplary guide block inaccordance with the embodiments of the present invention into the earcanal.

FIG. 4 illustrates various details of the guide block of FIG. 3.

FIG. 5 illustrates the stabilization of the guide block.

FIG. 6 illustrates pain inhibitor insertion and iontophoresisactivation.

FIG. 7 illustrates the placement of the combined TM penetrator anddelivery device.

FIG. 8 illustrates the penetration of the TM.

FIG. 9 illustrates the PE tube delivery.

FIG. 10 illustrates the removal of the combined penetrator and deliverydevice.

FIG. 11 illustrates the removal of the stabilizing impression.

FIG. 12 illustrates an exemplary guide block system in accordance withone embodiment of the present invention.

FIG. 13A illustrates further details of the guide block system of FIG.12; FIG. 13B is a transverse view corresponding to FIG. 13A.

FIGS. 14A-B illustrate detailed sectional views for the guide blocksystem of FIG. 12.

FIGS. 15A-C illustrate exemplary views seen by the endoscope of FIG. 12,when the guide block system is in place in the patient's ear.

FIG. 16 illustrates an anterior sectional view of the guide block systemin place in the patient's ear.

FIGS. 17A-F illustrate the deployment of the guide block system in placein the patient's ear.

FIG. 18 illustrates an exemplary support structure that is configured tosupport an iontophoresis module.

FIG. 19 illustrates an exemplary iontophoresis module in accordance withthe embodiments of the present invention.

FIG. 20 is an exemplary circuit diagram illustrating the electronicarchitecture of the iontophoresis module of FIG. 19.

FIGS. 21-22 illustrate an exemplary conceptual design for the combinedpenetrator and delivery device—Combined PE Tube Delivery Device (PETDD).

FIGS. 23-27 illustrate one embodiment of the actuator system for thecombined penetrator and delivery device—Combined PE Tube Delivery Device(PETDD).

FIGS. 28-32 illustrate an alternative embodiment for the Combined PETube Delivery Device (PETDD).

FIG. 33 illustrates one exemplary embodiment for an optical range finderfor the PETDD.

FIGS. 34A-B illustrate alternative embodiments for a range finder forthe PETDD.

FIGS. 35A-B illustrate an embodiment of a handheld device having thecombined features of an otoscope, guide tube stabilizer and rangefinder.

FIGS. 36A-B illustrate an embodiment of a dam for the working channelsof the guide block system.

FIGS. 37A-C illustrate an embodiment of a cam/eccentric mechanism toposition the PETDD in an X-Y direction.

FIG. 38B illustrates a curved hole without flaps formed in the TM byusing the hypo needle shown in FIG. 38A.

FIG. 39B illustrates a straight hole without flaps formed in the TM byusing the myringotomy spear shown in FIG. 39A.

FIG. 40B shows a wye pattern hole having flaps formed in the TM by usingthe trocar shown in FIG. 40A.

FIGS. 41A-C illustrate various PE tube shapes that include interruptedmedial flanges.

FIGS. 42A-B illustrate a PE tube that is delivered from the inside of acutting tool.

FIGS. 43A-B illustrate a grommet or T-tube type PE tube that isdelivered from the inside of a cutting tool.

FIGS. 44A-B illustrate a PE tube that is delivered on the outside of acutting tool.

FIGS. 44C-D illustrate flanges on a PE tube that have cut-outs to allowfor the easier passage and its deflection through the TM.

FIG. 45 illustrates an embodiment that combines the iontophoresismodule's electrode with the working channel or the vent tube of theguide block system.

FIGS. 46A-B illustrate the use of multiple longitudinal balloons thatare used to stabilize the guide block tubes within the ear canal.

FIGS. 47A-B illustrate the use of multiple circumferential balloons thatare used to stabilize the guide block tubes within the ear canal.

FIGS. 48A-B illustrate the use of a compliant balloon that is used tostabilize the guide block tubes within the ear canal.

FIGS. 49A-B illustrate the use of an offset balloon that is used tostabilize the guide block tubes within the ear canal.

FIGS. 50A-B illustrate the use of spokes in a balloon that are used tostabilize the guide block tubes within the ear canal.

FIGS. 51A-B illustrate the use of coil springs that are used tostabilize the guide block tubes within the ear canal.

FIGS. 52A-B illustrate the use of coils in a foam that are used tostabilize the guide block tubes within the ear canal.

FIG. 53 depicts an embodiment where a thin polymeric barrier is attachedto the distal end of the guide block.

FIGS. 54A-B illustrate the X-Y targeting and the Z distance measureswith respect to the ear canal.

FIGS. 55A-B illustrate a range finding and targeting embodiment thatincludes the use of a fine hair-like element mounted on the distal endof the guide block.

FIGS. 56A-B illustrate a range finding and targeting embodiment thatinvolve the use of lasers.

FIGS. 57A-B illustrate a range finding and targeting embodiment thatinvolve the use of optical methods.

DETAILED DESCRIPTION OF THE INVENTION

The embodiments of the present invention provide systems and methods forthe provision of painless, simultaneous, bilateral treatment of thetarget tissues of the ear of children suffering from recurrent otitis orotitis media with effusion in an office-based procedure in awake, mobilepatients, designed to manage the child's and the parent's anxiety.

In one aspect, the present invention is directed toward a suite ofmedical devices that shares a common support structure that is used toalign various therapeutic devices with the target tissues of the ear ofchildren. In one embodiment, the suite of medical devices can be used toinsert pressure equalization (PE) tubes in the tympanic membraneswithout reliance on general anesthesia. The novel suite of medicaldevices enable the performance of an in-office procedure for theplacement of PE tubes in a patient's tympanic membranes that does notrequire general anesthesia that can be completed within a short periodof time (e.g., 30 minutes); that can treat both ears at the same time(e.g., simultaneous bilateral); is suitable for young patients (e.g., 18months to 7 years old), where the management of anxiety and minimalinterventions are desirable. Such therapeutic procedures also benefitfrom the reduction of risks associated with the traditional surgicalprocedure.

The novel suite of medical devices that share a common support structureinclude devices for supporting, aligning and guiding the one or moremedical devices within the ear canal via a guide block; devices forpositioning the guide block; devices for stabilizing the guide block;devices for applying a local pain inhibitor to both ears beforeinitiation of the therapeutic treatment; devices for visualization; anddevices for penetrating the tympanic membranes and for delivering PEtubes. In addition, the common support structure is coupled with asystem that is used to preoccupy the patient with either or both of anaudio track, where the therapeutic treatment may be synchronized withthe audio track; or a video, where the therapeutic treatment may besynchronized with the video. In this manner, the child patient isdistracted while any combination of the above devices are beingutilized. For example, as the child patient is listening to a soundtrack for a video, the volume of the sound track is increased atcritical times, when the above devices could also create a loud noisethat would otherwise be heard by the patient had he/she not beendistracted by the sound track. Each of these medical devices isdescribed below in further details.

FIG. 1 illustrates the simplified support structure 1 that is worn onthe patient's head while the patient is awake and upright. The supportstructure 1 is configured to hold the one or more novel suite of medicaldevices 2 described above in alignment with the patient's ears 3. As canbe seen in FIG. 1, the support structure 1 can have an alignmentstructure with a first body engaging the first ear, a second bodyengaging the second ear, and a member extending around the head of thepatient between the first and second body.

FIGS. 2-10 illustrate a sequence of therapeutic procedures that can beundertaken by using the suite of medical devices that share a commonsupport structure that is used to align various therapeutic devices withthe target tissues of the ear of children. FIG. 2 illustrates views of asimplified ear canal. As can be seen in FIG. 2, the ear canal 10 isapproximately 19 mm long and has an average diameter of approximately 7mm. It has a non-uniform shape, terminating at the tympanic membrane 12or the ear drum 12. As set forth above, the suite of medical devices canbe used to insert pressure equalization (PE) tubes in the tympanicmembranes in a non-surgical procedure that does not require generalanesthesia. As a first step, FIG. 3 illustrates the insertion of anexemplary guide block 100 in accordance with the embodiments of thepresent invention into the ear canal 10. As is shown in FIG. 4 the guideblock 100 includes a foam block or disk 102 at its distal end. The foamblock 102 is configured to fit within the ear canal 10 near the tympanicmembrane 12. The foam block 102 holds in alignment a guide tube 104. Theguide tube 104 extends through the foam block and is configured to belocated near the tympanic membrane (TM). The guide tube 104 has a softtip 105 at its distal end. The foam block 102 also holds in alignment atube 106 that can be used to deliver medication into the space betweenthe foam block 102 and the TM. The tube 106 can also be used as a guidefor an image capture device such as an endoscope. The foam block 102also can hold in alignment a vent tube 108 that is used to vent thespace between the foam block 102 and the TM during the treatment of thespace. In addition, the foam block 102 also holds in alignment anelectrode and a low gauge electrical wire 110 to enable theiontophoresis module. As can be seen in FIG. 4, the inserted guide block100 fits within the ear canal 10, and the distal end of the guide blockis located near the tympanic membrane 12. In one embodiment, the guideblock 100 can be aligned to target PE tube placement using an in-situvision system that can be fed in through the tube 106. Alternatively,the vision system can be configured to support distance registration,such that the distance between the guide block 100 and the TM 12 can bemanaged.

FIG. 5 illustrates the stabilization of the guide block 100 within theear canal 10. The guide block 100 can be stabilized within the ear canal10 by the insertion of a hardenable material 120 about the guide block.The injectable material 120 has a workable state allowing adjustment toalignment between the guide block support structure and the targettissue of the ear. The injectable material 120 also has a hardened statefor stabilizing the guide block support structure relative to the targettissue. The workable state can be time dependent or activated. In oneembodiment, the impression material can harden in a matter of minutes.In other configurations, the impression material may be workable until ahardening agent is added, as is described below.

The stabilized guide block 100 can be used to receive modules with eachmodule capable of completing a different function. For example, thefirst module can be used for range finding/distance setting; then thatmodule can be removed from the guide block and a second module that canbe an iontophoresis unit is inserted. Thereafter, the iontophoresis unitis removed and the next (e.g., actuator module) can be inserted. Theguide block 100 can be used for a drug delivery/injection module foracute otitis media, and it can also be used for a PE tube deliverymodule for otitis media with effusion.

FIG. 6 illustrates the application of a local pain inhibitor to the earsfor example, before the myringotomy and the PE tube placement. In thismanner, the myringotomy and the PE tube placement can occur while thepatient is awake. The local pain inhibitor can be lidocaine with orwithout epinephrine. Once the pain inhibitor has been inserted into thedistal space between the guide block 100 and the TM 12 via tube 106 itis iontophoretically activated by coupling the electrode 110 to theiontophoresis module 4. The iontophoresis module can also be used in theear canal to deliver antibiotic and/or anti-inflammatory agents fortranstympanic delivery across inflamed tissue. The guide block 100 andthe iontophoresis module can be used for local delivery of not just apain inhibitor through the ear. The guide block 100 and theiontophoresis module can be used for local delivery of othertherapeutics such as mucolytics, antibiotics, steroids, surfactants, andso on, either before or after a myringotomy and/or a tympanocentisis, orprior to the piercing of the TM to help position and stabilize thetissue to aid in the actual incision. The drug delivery may also beuseful in the case of a retracted ear drum. The iontophoresis system isable to provide a well-tolerated method for providing anesthesia withlidocaine in a relatively short time to the patient that does not sufferfrom the symptoms associated with the systemic delivery of this drug.

FIG. 7 illustrates the placement of the combined TM penetrator anddelivery device 200, in accordance with one embodiment of the presentinvention. The combined TM penetrator and delivery device 200 can beinserted into the delivery system guide 104. The combined TM penetratorand delivery device 200 once in place can advance a lance 202 at itsdistal end to penetrate the TM membrane. Once the TM has beenpenetrated, the lance 202 can be retracted so as to deploy the PE tube204 (FIG. 9). It should be realized that the PE tube can be deployed atsame time and/or after the TM is penetrated, and not only after thelance is retracted. Furthermore, in some embodiments, the space in frontof and/or behind the TM can be aspirated before or after deployment ofthe PE tube.

After the delivery of the PE tube, the combined TM penetrator anddelivery device 200 is removed as illustrated in FIG. 10, and thereafterthe stabilizing material and the guide block are also removed, thusleaving the PE tube 204 in place in the TM, as illustrated in FIG. 11.Further details of each of these medical devices used in the aboveprocedures are described below.

Guide Block with Targeting and Visualization Systems

FIGS. 12-17 illustrate various aspects of the guide block. The guideblock in accordance with the embodiments of the present invention isconfigured to be inserted into the ear canal, and stabilized against thecartilaginous or bony portions of the ear canal. The guide block systemcan include a targeting element to ensure the combined TM penetrator anddelivery device is targeted at the correct location on the tympanicmembrane and to confirm the guide structure is located within a defineddistance from the tympanic membrane. The guide block system can alsoallow the insertion of an endoscope for visualization. The guide blocksystem can also include working channels for insertion of theiontophoresis system electrodes, the PE tube delivery device, suction,irrigation and other devices for delivery of therapeutic agents.

FIG. 12 illustrates the guide block system 100 in accordance with oneembodiment of the present invention. As shown in FIG. 12, the guideblock 100 has a foam block 102 at its distal end. The foam block 102 canbe dimensioned to have different outer diameters (e.g., at 2 mmincrements from about 3 mm to about 13 mm) to fit different size earcanals of adult patients as well as pediatric patients. The foam block'sthickness is selected to take up a minimum amount of axial space withinthe ear canal while providing enough thickness to provide a relativelysecure initial placement within the ear canal, act as a dam for theimpression material, and act as a dam for the Lidocaine and epinephrineand prevent the solution from exiting the ear. The foam block or diskallows for the variable positioning within the cross section of the earcanal. The foam block 102 can be compressed during the insertion of theguide block 100 to minimize patient discomfort resulting from the foamdisk contacting the ear canal. The slow recovery properties of the foamallow it to stay compressed during insertion and then expand to fill thecross section of the ear canal once proper placement is attained. Thefoam disk 102 can then act as a dam, preventing the impression materialfrom flowing into the space between the foam disk 102 and the TM. Inaddition to the closed cell foam described above, the disk 102 can bemade of a soft, open cell foam. The soft open cell foam can beconstricted with a sheath that can be pulled back to spring open thefoam—which will act as a dam. The foam will spring quickly—unlike the“slow” release of the closed cell foam. The sheath can be a tube runningthe entire (or close to the) length of the guide block lumens. It canalso be a short sleeve with strings or other means so that when thesleeve is pulled back, it leaves the main shaft free for adherence tothe impression material. The sheath can also be “tear away” in style.

FIG. 12 also shows that the guide block system 100 is configured tocooperate with an electrode 110 for the iontophoresis module, anendoscope 121 for visualization, and a fill nozzle 130 for deliveringthe impression material into the ear canal.

FIG. 13A illustrates further details of the guide block system of FIG.12, and FIG. 13B is a transverse view corresponding to FIG. 13A. Asshown in FIGS. 13A-B, the guide block 100 includes a working channel104, an endoscope channel 112, and one or more vent tubes 114. At theproximal end of the working channel 104, the guide block 100 includes aone way valve 124, and at the proximal end of the endoscope channel 112,the guide block 100 includes an endoscope clamp 122. The one way valve124 allows the iontophoresis solution to be injected into the spacebetween the distal end of the guide block 100 and the TM without theiontophoresis solution leaking back out of the working channel 104. Inone embodiment, the one way valve is configured to seal around theiontophoresis electrode when it is placed in the working channel. Theendoscope clamp 122 allows the endoscope to be locked in position withrespect to the guide block so as to stabilize the endoscope image andfree the operators one hand.

FIGS. 14A-B illustrate detailed sectional views for the guide blocksystem of FIG. 12. FIGS. 14A-B show one exemplary arrangement for theelements of the guide block 100. FIGS. 14A-B also show that a sleeve 126can surround the working tube 104, the vent tubes 114, and the endoscopechannel 112. In addition, FIGS. 14A-B also show that an adhesive layer128 is used to connect the sleeve 126 with the foam block 102; and thatthe sleeve 126 includes an adhesive layer 129 on its internal surface tohelp securely hold the working tube 104, the vent tubes 114, and theendoscope channel 112.

The working channel 104 can be made from a medical grade transparentplastic tubing. The working channel 104 is the conduit for the deliveryof iontophoresis solution, the iontophoresis electrode, and theinjection of irrigation solution. The working channel 104 is also theconduit for delivering the combined TM penetrator and delivery device200 near the target tissue region. The working channel 104 is also theconduit for delivering the targeting apparatus near the target tissueregion. The distal end of the working channel 104 can be tapered down toprevent the insertion of auxiliary devices past the distal end of theworking channel so as to prevent any accidental damage to the TM. In oneembodiment, the preferred length of the working channel is between 5-10cm and preferably about 7 cm.

The endoscope channel 112 can be made from a medical grade transparentplastic tubing to allow visualization through the walls and it is sizedto fit a small (i.e. 1 mm) flexible endoscope. The transparency and theresulting visualization is useful to check for voids in the impressionmaterial, bubbles in the local pain inhibitor, and align the image onthe endoscope monitor with the position of the guide block. Theendoscope image can be registered by use of colors or features on otherguide block components.

The one or more vent tubes 114 allow air to escape as iontophoresissolution is inserted, prevent excessive pressure on the tympanicmembrane during iontophoresis solution injection, and are also used torelieve any negative pressure within the ear canal as any device isremoved from the ear canal. The vent tubes 114 are sized to allow reliefof pressure, which can be positive during injection of iontophoresissolution and negative during the guide block removal. The vent tubes 114are sized to allow relief of pressure with a minimum amount ofresistance while maintaining a small cross sectional area so thatsurface tension would not allow the iontophoresis solution to leak backout of the working channel 104. The wall thickness for all the tubes andchannels is chosen to ensure an adequate column strength during theirinsertion to be resistant to buckling or crushing, yet be strong enoughto maintain flexibility and have a minimal cross sectional footprint.Ribs, bumps, or other protrusions may be added along the length of theguide block tubes and channels to help create an interlock with theimpression material.

FIGS. 15A-C illustrates exemplary views seen by the endoscope of FIG.12, when the guide block system is in place in the patient's ear. As setforth above, the endoscope image can be cross-referenced by use ofcolors or features on other guide block components. FIG. 15A shows thevent tubes 114 as seen by the endoscope through the transparentendoscope channel 112. The TM can also be seen. FIG. 15B shows thecolored working channel 104 as seen by the endoscope through thetransparent endoscope channel 112. The TM can also be seen. FIG. 15Cshows an image where a stripe of color in the endoscope channel 112 canhelp orient the observer of the endoscope image.

FIG. 16 illustrates an anterior sectional view of the guide block system100 in place in the patient's ear. As is shown on FIG. 16, the guideblock is in place in the right ear. Impression material 120 fills inaround the guide block system to secure it in place. The foam disk 102is placed lateral of the TM 12 and within the bony or cartilaginousstructure of the ear canal. The impression material 120 is injected intothe ear canal around the tubes of the guide block, filling the ear canaland extending into the concha or the outer ear. The impression material120 helps stabilize the guide block with respect to the TM. The workingspace 150 between the guide block 100 and the TM 12 can be filled withthe iontophoresis solution.

The fill nozzle 130 is used to deliver the impression material. The fillnozzle 130 can be placed external to or near the inside of the earcanal. The fill nozzle 130 can have a large bore and a tapered distalend, so as to ensure a complete fill of the ear canal space around theguide block by maximizing the velocity and momentum of the impressionmaterial 120 as it leaves the fill nozzle 130. Alternatively, the fillnozzle 130 can be placed deeper in the ear canal and retracted as theear canal fills with the impression material, so as to ensure a completefill by filling in the ear canal from next to the foam disk 102 first.The fill nozzle 130 can have one or more offset holes near its distalend that may be located on the side walls of the fill nozzle 130 inaddition to or in place of an axial hole at the distal end of thenozzle. The one or more side holes for the fill nozzle 130 can improvethe safety of the device since with this arrangement the impressionmaterial is not injected directly at the foam disk 102, which could leadto the leaking of the impression material past the sides of the foamdisk 102. The one or more side holes for the fill nozzle 130 can helppromote a complete fill by better reaching pockets or voids that couldbe blocked otherwise. Alternatively, more than one fill nozzle may beused to circumferentially surround the guide block to ensure a betterand more complete fill. The one or more nozzles could issue from acommon header or could be separate fill nozzles. There can also be alumen in the guide block for filling. In that case, the fill nozzle canbe connected to the guide block and thus could fill from the block backto the opening in the canal. This can ensure consistent filling andelimination of voids.

The fill nozzle can have depth and orientation markers to that theposition of the tip hole(s) could be detected even when the tip is notvisible. The depth and/or orientation markers can be placed on theproximal portion of the fill nozzle 130. The depth markers can line upwith portions of the guide block to indicate that the tip of the nozzleis adjacent to the foam disk 102. Orientation markers that may beseparate or combined with the depth markers can be used to indicate theorientation of the nozzle hole(s).

FIGS. 17A-F illustrate the deployment of the guide block system in placein the patient's ear. FIG. 17A shows that the foam disk 102 iscompressed before the guide block is inserted under endoscopicvisualization (FIG. 17B). Then in FIG. 17C, the ear canal is filled withthe impression material. In FIG. 17D, once the impression material hashardened, a solution containing the pain inhibitor is injected into theworking space. In FIG. 17E, the iontophoresis electrode is inserted todeliver the iontophoresis. Then at FIG. 17F, the guide block and theimpression material are removed.

The guide block system is also configured to enable the visualization ofthe iontophoresis electrode(s). In order to achieve this, the tip of theiontophoresis electrode is visible via the endoscope to ensure that theelectrode is in contact with the iontopheris solution and not surroundedby a bubble or air pocket which could reduce the anesthetic effect.

Certain aspects of the embodiments of the present invention are directedtoward features that can prevent the impression material fromencroaching past the distal end of the guide block. As described above,the guide block system includes a foam disk mounted on the distal end ofthe guide block tubes so as to prevent the impression material formflowing into the space between the distal end of the guide block and theTM. FIG. 53 depicts an embodiment where a thin polymeric barrier isattached to the distal end of the guide block. In accordance with thisembodiment of the present invention, the foam disk 102 can be augmentedor even replaced by a thin polymeric barrier 162 that is attached to thedistal end of the guide block 100. The thin polymeric barrier 162 isopen at its proximal end, and it is configured to fit into the ear canallike a trash bag would fit in a trash can. When the impression material120 is injected in the proximal opening of the barrier 162, it flowsinto the ear canal, expanding the barrier 162 against the walls of theear canal 10. The barrier 162 will prevent the flow of the impressionmaterial 120 past the distal end of the guide block 100, since thebarrier 162 is closed and attached with the guide block at its distalend. The open end of the barrier 162 can be dimensioned to be large asshown or small, such as a luer fitting. The impression material can alsobe injected into a compliant balloon or pouch placed on the guide blockworking channel or vent tubes. In this configuration, the impressionmaterial would be prevented from moving into the space between the guideblock and the TM.

Various additional details for the guide block system described aboveare provided below. As described above, the guide block system is usedin a highly variable anatomy of the ear canal to provide a stableplatform for subsequent steps requiring precision and accuracy, forexample for the placement of PE tubes. Accordingly, the placement andthe fixation of the guide block should preferably be quick. The fixationshould be secure and rigid with respect to the TM, and the guide blockdeployment needs to be able to fill complex, non-centric and sensitiveregions in the ear canal in order to fix the guide block in place. Forexample, the foam disk that is used at the distal end of the guide blockis compressed for a low profile during delivery to avoid contact withthe sensitive ear canal wall. However the foam disk then expands to fillthe space between the guide and the ear canal. The foam disk can be amemory foam. The memory foam can be a slow recovery urethane or vinylfoam similar to those used in ear plugs. The advantages of the memoryfoam are that it is simple, currently available, low in cost and easilyproducible in a range of sizes. The impression material can be acatalyzing foam. The catalyzing foam can be a two-part foam that usesthe addition of two components to produce the foam which can set uprapidly in the ear canals. The advantages of the catalyzing foam arethat it has a very low profile during delivery, it can fit into anyshape canal and it can be formulated to have varying hardening speeds.In addition to the use of catalyzing foams to stabilize the guide blocksystem within the ear canal, the following alternative stabilizationschemes are also within the scope of the embodiments of the presentinvention. These alternative stabilization schemes include the use ofballoons, deformable mechanical elements, and bulk material fills, andare described below.

FIGS. 46A-B illustrate the use of multiple longitudinal balloons 570that are used to stabilize the guide block tubes within the ear canal.The use of balloons is advantageous in that the balloons have a lowprofile during their insertion; they are quick to set up and take down.In addition, the use of balloons enables the stabilization of the guideblock in different shaped and sized ear canals. The arrangement shown inFIG. 46A-B allows for the guide block tubes to be placed offset in theear canal via selectively shaped or inflated balloons.

FIGS. 47A-B illustrate the use of multiple circumferential balloons 572that are used to stabilize the guide block tubes within the ear canal.The arrangement shown in FIGS. 47A-B can be used to fit the varyingdiameter of the ear canal along its length by expanding balloons atseveral locations. The advantages of this embodiment are that theballoons do not have to contact the sensitive areas of the ear canal; arange of ear canal sizes and configurations can be handled with onedevice; and the sequential inflation of the tubes may allow for betteradjustment of the dominant axis of the guide block tubes with respect tothe target location on the TM.

FIGS. 48A-B illustrate the use of a compliant balloon 574 that is usedto stabilize the guide block tubes or act as a dam within the ear canal.As is shown in FIGS. 48A-B, a single balloon can expand to gently fillthe entire space between the guide block tubes and the ear canal, in amanner similar to a latex compliant balloon catheter.

The balloon-based schemes for the stabilization of the guide block canhave the one or more balloons filled with air, water, saline or similarmaterial. Alternatively, the balloons can be filled with othersubstances for more secure anchoring by means of a more rigidballoon(s). One such filling can be a two-part reaction system, where aballoon is first filled partially with a one substance and then thesecond substance is added. The two substances react chemically to form aharder substance. Either of the substances can be in powder, liquid orgas form. Another such filling can be a two-part or a one-part systemthat reacts and expands in volume to ensure a complete fill of the earcanal volume while not placing excessive pressure on the ear canal.Another such filling can be a two-part or a one-part system where thefill is UV-activated. Additional substances may be introduced at the endof the guide block stabilization procedure to promote the removal of theexpanded balloons.

FIGS. 49A-B illustrate the use of an offset balloon 576 that is used tostabilize the guide block tubes within the ear canal. As can be seen inFIGS. 49A-B, in order to allow for non-concentricity of the guide blocktubes with respect to the ear canal, the balloon 576 is not concentricwith the guide block tubes. The use of the non-concentric placement ofthe guide block tubes with respect to the balloon(s) can also beimplemented with the embodiments depicted in FIGS. 47-48 above.Furthermore, the non-concentric placement of the guide block tubes withrespect to the balloon(s) can also be implemented with offset hole(s) ina foam block.

As set forth above, one alternative stabilization scheme includes theuse of deformable mechanical elements. The deformable mechanicalelements include structural elements that are displaced so that therestorative force of the elements acts on the ear canal walls tostabilize the guide block system. The use of the deformable mechanicalelements can be combined with foam or balloon-based methods describedabove.

FIGS. 50A-B illustrate the use of spokes in a balloon that are used tostabilize the guide block tubes within the ear canal. As is shown inFIGS. 50A-B, malleable spokes or ribs extend between the guide blocktubes and the balloon surrounding the guide block tubes such that thespokes guide the inflation of the balloon when, for example, when theballoon needs to be non-concentric with respect to the guide blocktubes.

FIGS. 51A-B illustrate the use of coil springs that are used tostabilize the guide block tubes within the ear canal. As can be seen inFIGS. 51A-B, a coiled spring are dimensioned to fit in the ear canal,whereby the restorative force of the spring tries to maintain thecylindrical shape, thus stabilizing the guide block system in the earcanal.

FIGS. 52A-B illustrate the use of coils in a foam that are used tostabilize the guide block tubes within the ear canal. As is depicted inFIGS. 52A-B, spring elements in the foam in the form of coil ribs aid inthe expansion speed and force of the stabilizing scheme.

As set forth above, one alternative stabilization scheme includes theuse of bulk material fills. As described above, one stabilization schemeinvolves the use of catalyzing foams to stabilize the guide block systemwithin the ear canal. One type of catalyzing foam is a two-part vinylpolysiloxane impression material that is injected into the ear canalaround the guide block tubes as a viscous material which then hardensover time to provide for the anchoring of the guide block system withinthe ear canal. Based on known otological methods and material, thisimpression-material scheme is able to fill the ear canal space with aminimal amount of pressure on the ear canal. The known methods andmaterial can be enhanced in order to reduce patient discomfort bymodifying them to increase the speed of cure or the hardness of the cureby accelerants that include the use of chemically reactant accelerants,electricity, UV and/or heat. Heat as used herein provides additionalbenefits, in that the warming of materials to near body temperature canbe more comfortable for patient, and the lower temperature difference isless jarring on the patient. Additionally, heat can also allow thestabilization material to potentially flow faster and thus enable abetter fill.

Certain aspects of the embodiments of the present invention are directedtowards methods and devices for preventing or minimizing the abrasion ofthe ear canal while allowing for the penetration and the stabilizationof the guide block within the ear canal. FIGS. 36A-B illustrate anembodiment of a dam for the working channels of the guide block system.FIG. 36 A shows a portion of the working channels 104 of the guide blocksystem 100 inside the ear canal 10, and the relative position of thedistal end of the working tubes with respect to the TM 12. As can beseen, a dam structure 170 can be used at the distal end of the workingchannels 104. The dam structure 170 is shown in its collapsed state asit is being inserted into the ear canal 10. Once in place, the damstructure 170 is shown in its non-collapsed or deployed state. The damstructure 170 can be composed of a soft and smooth material (e.g.,silicone) that is shaped to create a shroud-like structure that can besupported by a scaffold structure 172 that is internal or adjacent tothe dam structure 170. The scaffold structure 172 can be deployed viaactuation cables that are accessed through the working channels. Inoperation, using the above-described dam structure 170, the workingchannels 104 can be advanced into the ear canal in a “no-scrape” stateand then deployed against the ear canal 10 in a radial direction, thusminimizing abrasion and discomfort to the patient. Alternatively, adelivery sheath made of a very soft material that minimizes the abrasionof the ear canal can be used to encompass and deliver the guide blocksystem into the ear canal, in a manner similar to how a self expandingstent is deployed. The very soft material can be made from collagen.

Iontophoresis System

One medical device that can be supported by the support structure 1 isan iontophoresis module 4, illustrated in FIG. 18. FIG. 18 illustratesthe support structure of FIG. 1 when configured to support aniontophoresis module 4. As can be seen in FIG. 18 the iontophoresismodule 4 is aligned near the external ear 3, and includes a stabilizingunit and a ground electrode 5 and a battery area 6, as well as aniontophoresis unit with its associated electrodes, and ear plug andinjection ports 7. The iontophoresis module 4 includes an injection port8 and a ventilation port 9. The stabilizing electrode element can beconfigured to be worn around the ear. The ground electrode 11 can beworn behind the ear and can stay in alignment by use of biocompatibleadhesive. The ear piece portion 12 can be configured to sit in theopening of the ear canal and close the canal and enable fluid injectionand venting. The electrode wire can be formed or annealed to apredetermined shape to fit comfortably around the ear of the patientsimilar to miniature ear phones used with cell phones and otherelectronic devices.

FIGS. 19-20 are used to illustrate various aspects of the iontophoresismodule. As shown in FIG. 19, the iontophoresis module 300 in accordancewith one embodiment of the present invention can be a battery powereddisposable electronic device 310 that provides regulated current to twoelectrodes (one for each ear) 302A-B with a single return electrodepatch 306. The electrodes 302A-B are configured to fit within the guideblock one electrode for each guide block. The regulated current is usedfor the iontophoresis process, which applies local anesthesia or othertherapeutic compounds to the tympanic membrane. As shown in FIG. 19, theiontophoresis module 300 can be a small electronic device, about thesize of a business card, with a LCD display 308 and several buttons 312for operation. Furthermore, the iontophoresis module can be co-locatedwith the return electrode patch to minimize the amount of loose wiresand overall package size. In this embodiment, the return electrode patchwould be permanently or by means of a metal snap or other electricallyconductive attachment mechanism attached to the iontophoresis module,and the entire assembly then adhered to the patient's skin (e.g. at theback of the neck) via the return electrode patch, thereby fixing theiontophoresis module in a location easily accessible to the physicianbut not easily accessible to the patient.

FIG. 45 illustrates an embodiment that combines the iontophoresismodule's electrode with the working channel or the vent tube of theguide block system. As is shown in FIG. 45, the tube 104M has conductiveregions at its tip and tail, and is insulated in between. Thisconfiguration of combining the iontophoresis module's electrode with theworking channel or the vent tube of the guide block system can eliminatethe need to deliver a separate electrode through the working channel orthe vent tubes, thus speeding up the procedure.

The operation of the iontophoresis module 300 is described below. Theuser can turn on the iontophoresis module by pulling on a small plastictab from the back of the unit. This tab is designed to keep thebatteries from powering the circuitry until desired. Upon pulling thetab the batteries will begin powering the circuitry and the LCD 308 willilluminate. Next, the user can clip the unit to the back of thepatient's collar via the clip on the back of the housing. Once thehousing is set, the return electrode patch can be placed on the back ofthe neck. The next step is to apply the anesthesia solution into thepatient's ear and position the electrode. Once completed on one side,this side can be activated independently of the other ear. If, forexample, the left electrode is placed first, the user will press the“Left Ear Start” button on the main unit to begin the automaticpre-programmed current delivery sequence, starting with a currentramp-up from zero. Meanwhile, the user can place the right ear electrodeinto the patient's right guide tube. Once properly placed, the user canpress the “Right Ear Start” button to independently begin currentdelivery to the right ear. A progress meter can be displayed for eachear on the LCD 308. The progress meter is represented by the filled inarea of a box, that starts empty and fills in as the charge is delivereduntil is it fully filled and the process is complete. Once currentdelivery starts, the user waits for the device to signal it is finishedor there is a problem via an auditory beep sound. After the devicedelivers the full dosage of current to each ear, the progress meter foreach ear is filled and the system can deliver a short series of threebeeps to signal successful completion. Once the device signals it iscompleted it can automatically shut down. At this point, the user canremove the electrodes, and can start the process of removing the excesslidocaine and cleaning the area. Again, this can be done independentlyon one side without affecting proper device operation on the other side.

At any time during the process the current delivered to an electrode canbe paused by pressing the left or right button. The system will rampdown the current to that electrode. The user can also pause bothelectrodes at once by pressing the stop button. This will cause thesystem to ramp down the current to both electrodes. In either case theuser can continue with the procedure by pressing the left or rightbuttons. This will cause the system to ramp up the current for thatelectrode and continue delivering the total charge where it left offbefore being paused. At the end of the iontophoresis current deliverycycle, the current will ramp down to zero. Once both sides havecompleted iontophoresis and the electrodes have been removed, the returnpatch can also be removed and the entire unit discarded. Power canautomatically shut off after one hour of time, or any selected unit oftime. The unit is designed to allow only one use and can not be turnedback on. Another embodiment disables the current delivery function aftera single use, but then enables additional functionality, such as a game,a clock, etc. for the patient's use after the procedure. If there is anerror the system can emit a series of long beeps continuously.Alternatively, or in addition to the series of long beeps, visual meanscan be used, so as not to disturb the patient. For example, a blinkinglight located on the back of the unit or other hard to reach place wouldlikely not be noticed by patient. Conditions that could cause such anerror include: a detected open circuit or an over current condition. Inthe case of an open circuit, the device will automatically stopdelivering current to the patient through a controlled current ramp downand the user can resume delivery by pressing the appropriate startbutton. In the case of over current, the device has detected an internalerror, will automatically stop all current to both electrodes, will notrestart, and the device should be discarded. For both cases anappropriate message is displayed on the LCD screen 308.

FIG. 20 is an exemplary circuit diagram illustrating one electronicarchitecture for the iontophoresis module of FIG. 19. Once the plastictab is removed from the back of the unit, the two 3V batteriesimmediately begin to power the circuit. The battery supplies the LP2975voltage regulator which delivers a very stable 5V output. The 5V outputis used to supply the microprocessor (e.g., Atmel ATtiny 261), thedigital-to-analog converter (DAC) converter (e.g., Maxim MCP4922), thecurrent sensing operational amplifiers (e.g., LM358), and all componentsof the operator interface (buttons, buzzer, LCD). The microprocessorcontrols the majority of the functions of the emergency stop button toramp down current to both electrodes; analog inputs for sensing currentdelivered to each electrode; serial peripheral interface (SPI)communications to set reference for the DAC; control signals for buzzerand LCD. External to the microprocessor, the 6V battery power drives theMAX5028 DC-DC converter which converts the battery voltage to a 30Voutput. This output is used as the rail power for the constant currentunit. The constant current unit can be designed using one of twoalternatives. The first alternative uses an Operational Amplifier(Op-Amp) such as LM358 which converts a differential input voltage (thecontrol signal) to an output voltage, and eventually to a current basedon the chosen sense resistor. The second technique uses OperationalTransconductance Amplifiers (OTA) which operate in a manner similar toan Op-Amp in that it is controlled by a differential input voltage, butit drives an output current based on a biasing current providedexternally.

The microprocessor sets a reference voltage level to the current sourceusing a DAC. The microprocessor communicates to the DAC via a serialprotocol SPI. The constant current source uses a control signal (0-5V)from the microprocessor to ramp 0 to 1 mA of current according to apredetermined ramp shape. The DC-DC converter provides a high enoughrail voltage (30V) to allow the constant current source to drive 11 mAof current based on a maximum expected body resistance of 22.5 kOhms.The body resistance is based on research performed by the assigneeherein. After the allotted delivery time the microprocessor ramps thecontrol signal back down to 0V which reduces the current delivered bythe current source back to zero.

The system uses an LM358 Op-Amp on each electrode line to measure thecurrent delivered to the patient. The Op-Amps are connected toanalog-to-digital converters internal to the microprocessor. This givesfeedback information to the microprocessor for sensing of open circuitswithin the electrode circuit and to calculate total charge delivered tothe patient. For safety, the current sensing Op-Amps in parallel withthe output electrode also drive an over current monitor. If a faultoccurs and current increases beyond a set limit of 1.5 mA due to someinternal failure, the transistor in the over current shunt will open andallow the increased current to bypass the load, the patient in thiscase, and safely return to the cathode (negative terminal) of thebattery. The microprocessor will independently detect the over currentcondition, shut down the current source, and inform the operator of asystem fault.

After the system has completed delivering the total charge to thepatient it goes into a finished state and begins a timeout count. At theend of the timeout count the firmware turns off the system and cannot beturned back on. The microprocessor includes EEPROM memory that iswritten to when the system is turned on initially. If the system isre-powered, for instance, by forcibly replacing the batteries, thefirmware will detect that it has been powered before and will not turnon again. This scheme is to ensure the device is one time use only. Themicroprocessor includes internal brown out detection to detect if thesystem voltage is below nominal. This detection is used by the firmwareto disallow the system to begin or complete operation if the system doesnot have enough power (e.g. if the batteries are drained).

Another embodiment of the iontophoresis device combines theiontophoresis activation with the delivery of the anesthetic solution.Such an embodiment includes a syringe-like device that delivers theanesthetic solution and is coupled with an iontophoresis activationmechanism such that the iontophoresis is actuated upon complete deliveryof the anesthetic solution.

Certain aspects of the embodiments of the present invention are directedtoward novel uses for the iontophoresis module. In accordance with oneembodiment, the iontophoresis module can become a game or a clock afterits single use. As described above, the iontophoresis module can bedesigned for single patient use, such that after it has deliveredtherapeutic current to one or both ears, the current-producingcapabilities can be disabled. However, the device can retain batterypower that would allow it to power additional functionality. Forexample, after a single use, the current producing capabilities aredisabled and a clock feature can be enabled. The patient can take theunit home and use it as a clock. Additional functionality could alsoinclude an interactive game, that incorporates the use of the controlbuttons and feedback via the display screen. Physicians could start thepatient playing the game, distracting the patient from subsequentprocedural steps. The patient could then take the game device home, thusbuilding a positive perception of the experience.

Certain aspects of the embodiments of the present invention are directedtoward the geometry of the iontophoresis modules electrodes. Inparticular one aspect of the embodiments of the present invention isrelated to the distance the electrode is protruding beyond the distalend of the guide block into the distance between the distal end of theguide block and the TM. The results of test show that when the endoscopeis flush with the end of the guide block, and the electrode protrusionis 2 mm, the edge of the electrode tip is barely visible in theendoscope image; when the electrode protrusion is 3 mm, its tip isvisible; when the electrode protrusion is 4 mm, its tip is easily seenand when the electrode protrusion is 7 mm, the electrode appears to bealmost at the center of the endoscope image. Accordingly, it ispreferred to have the electrode tip protrude beyond the distal end ofthe guide block by about 4-6 mm. In addition, it is preferred that theelectrode ends be symmetric to avoid operational errors if the electrodeis connected backward.

Combined TM Penetrator and PE Tube Delivery Device (PETDD)

The PETDD provides a system for cutting the tympanic membrane andplacing a PE tube inside the incision. The delivery device is configuredto fit within the guide block system and is compatible with the PE tubedesign. The portion of the device that is inserted in the guide blocksystem (including the cutting surface) can be disposable. The drivemechanism and its controls can be durable or disposable. The drivemechanism and its controls are configured to control the speed andmotion of actuation to minimize sound and or sensation on the TM and tothe patient. For example, a low speed drive and actuation may have a lowfrequency motion of the TM and thus cause a low sensation to patient. Inaddition, the presence of fluid or gel in space against TM may also helpdampen any vibration against the TM. The penetrator device can also beconfigured to include suction in the device. For example, suctioncapability provided through a needle can enable suction at same time astube placement to remove fluid behind the TM. Suction may also offer amore stable TM for piercing with the actuator.

FIGS. 21-22 show an exemplary conceptual design for the PETDD 230. Inone embodiment, the PETDD 230 includes two small mechanical actuatordevices 200 that can cut the TM and place the PE tube within the cut.The mechanical actuators can be driven by an external linear actuator232 through a flexible coupling 234.

As one alternative, the external linear actuator 232-234 can be aseparate, durable device that can be hung on the back of the examinationroom chair or placed on a counter next to the endoscope equipment. Themechanical actuators are preferably sterile, disposable devices with thePE tubes preinstalled.

In operation, once the iontophoresis process is complete, the user willremove the iontophoresis electrodes and drain the ears of all lidocaine.Optionally, the guide block system can be used to rinse out the spaceand clean out the lidocaine with saline or water so as to remove tracesof lidocaine. The rinsing or cleaning can prevent or minimize theundesirable sending of the anesthetics into the middle ear and evenpossibly into the inner ear. The user will then remove the PETDDactuators 200 (and attached cables 234) from their sterile packaging.The user will insert one PETDD actuator 200 into the working channel ofthe guide block system. While watching the endoscope display, the userwill insert the PETDD actuator 200 until it is within range of contactwith the TM. The user will continue to push on the actuator 200 until ithits a stop on the guide device. The piece near the TM will moverelative to the rest of the actuator, so that it does not puncture theTM. Once the actuator is in place, the user can lock the actuator (e.g.,by using a twisting motion). Once locked, a range finding piece will belocked to the actuator housing and the guide device. The user will thenrepeat the same process with the other ear. Once the PETDD actuators 200are inserted in both ears, the user will connect the cable ends of eachactuator 200 into the drive unit, i.e. controller, 232. The user willthen confirm proper positioning of both PETDD actuators using theendoscope. Once positioning is confirmed, the user will press theactuation button 233, i.e. input device, on the drive unit. The inputcommand delivered by the user will send a signal to the drive unit andthe drive unit will provide simultaneous linear actuation of both PETDDactuators. The controller, in response to the input command, may also beconfigured to synchronize the simultaneous therapeutic remodeling withan audio track and/or with a video shown on a video source 235 (depictedin FIG. 18) oriented toward the patient. The actuators can then cut theTM, and optionally also insert the PE tubes and then retract the cuttingtools while leaving the PE tubes in place. The drive unit will indicatethat the placement is complete. The user will then remove the guideblock system from each ear and inspect the results.

In one embodiment of the PETDD and its related drive system, the driveand motion coupling functions are included in an external, durabledevice 232 and the range finding, cutting, and placement functions areincluded in a device that fits within the guide block system. As usedherein, the component that fit within the guide block is called theactuator system. The external device is called the drive system.

One exemplary PETDD and its related drive system can have the followingcomponents, namely: a drive—a component that provides the basic motionto the device, and which can be external to the ear canal; a motioncoupling—a component that transfers the motion from the drive to themotion for the device in the ear; if necessary, the component can alsoconvert the type of motion provided by the drive to the motion requiredfor actuation (i.e. convert rotary motion to linear motion); the rangefinder—a component that provides a means to verify that the deliverydevice is within the designed range of the TM; this component may or maynot contact the TM; a cutting tool—a component that makes the designedincision in the TM in which the PE tube is placed; and a tube delivery—acomponent or assembly of components that deploys the PE tube andsecurely places it in the cut.

Actuator System

The Actuator can be mechanical, hydraulic, pneumatic, orelectro-mechanical in nature. FIGS. 23-27 illustrate one embodiment ofan exemplary actuation system 200. As shown in FIG. 23, the actuationsystem includes a PE tube 550 that rides on the outside of a cuttingtool 552. The cutting tool 552 can make an incision and then the PE tube550 is pushed through the incision until the internal (distal) flange isin the middle ear space. The cutting tool 552 is then retracted and thePE tube 550 is left in place. The PE tube 550 internal flange is shapedat an angle to help open the incision as it passes through. The entireactuator housing 556 is designed to sit within the guide block's workingchannel, which is inserted and stabilized within the ear canal.

Certain components shown in FIG. 23 are also used to implement the rangefinding capability of the actuator system. In one embodiment, theactuator system uses a passive range finding technique. The so-calledcontact piece 564 contains the cutting tool 552 and the PE tube 550 andrides within the actuator housing 556. A low force spring 566 is used toput a small preload on the contact sheath 568. As the user slides theactuator unit into the working channel of the guide block, the contactsheath 568 contacts the TM and compresses the spring 566 until the guidepiece is firmly seated on the hard stop in the guide device. At thispoint, the contact sheath 568 is touching the TM and the cutting tool552 is a fixed distance from the end of the contact piece 564, andtherefore, the TM. The spring 566 is designed so that the force appliedto the TM will not cause any damage or discomfort to the patient. Atthis point, the contact piece 564, cutting tool 552, and PE tube 550need to be locked to the guide piece. The locking piece, shown in FIG.23, provides the locking mechanism. FIG. 24 illustrates the exemplaryactuator in the un-locked state. FIG. 25 shows the actuator in thelocked state. The locking piece 570 contains two blade-like elementsthat, when rotated, cut into an elastomer element on the contact piece564, locking the contact piece in the axial direction. Once locked, thecutting plunger 558, cutting tool 552, snap piece 560, and PE tube 550move independently from the contact piece 564 and the guide piece. Theactuator is now ready to cut and deploy.

FIG. 26 shows the actuator device fully deployed, with the cutting tool552 against a hard stop 562 created between the snap piece 560 and thecontact piece 564. The snap piece 560 has two “legs” that snap out andcreate a locking mechanism so the snap piece is not retracted when thecutting tool 552 is retracted. FIG. 27 shows the actuator device withthe cutting tool 552 retracted after PE tube 550 deployment. The snappiece 560 keeps the PE tube 550 from pulling back with the cutting tool552, leaving the PE tube properly placed in the TM incision. At thispoint, the actuator or the entire guide device can be safely removedfrom the ear.

Motion is applied to the actuator using a cable within a sleeve. Twosleeves are used: an inner sleeve to provide the twisting motion neededto lock the contact piece and an outer sleeve to provide structuralsupport.

The exemplary cutting tool geometry is shown as a simple, spear-likecutting tool, similar to a myringotomy spear. Other cutting toolgeometries may also be used. One preferred cutting tool in the form of amyringotomy spear was found to have very good cutting characteristics,including a low cutting force, clean cut, and not impacted significantlyby TM angle, TM size, and cutting speed. Other types of cuttinggeometries, such as spinal needles and trocar needles can create flapsafter cutting through a membrane. These flaps can increase the potentialfor skin cells to enter the middle ear space; however potential benefitsof these forms include providing increased open area through which thePE tube can be inserted, thereby reducing the amount of force exerted onthe tympanic membrane and thus reducing sensation for the patient (asshown in FIGS. 38-40). The cutting tool may be actuated such that themyringotomy is specifically oriented relative to the structures of thetympanic membrane, for example in a radial or transverse direction.

FIGS. 38-40 illustrate various myringotomy/tympanostomy hole shapes thatcan be made in the TM using various different cutting tools. FIG. 38Bshows a curved hole without flaps formed in the TM by using the hyponeedle shown in FIG. 38A. FIG. 39B shows a straight hole without flapsformed in the TM by using the myringotomy spear shown in FIG. 39A. FIG.40B shows a wye pattern hole having flaps formed in the TM by using thetrocar shown in FIG. 40A.

An exemplary drive system can include the following components: a DCmotor drive; reduction gearing driving two lead screws, one for eachactuator unit; a connector to covert linear motion of the lead screw tolinear motion of the motion coupler between the drive system and theactuator units; an AC inlet power module and AC-DC power supply; aprinted circuit board (PCB) with control electronics; an enclosure withsuitable user interface and possible mounting bracket to hang on back ofexamination chair.

Other drive system mechanisms are possible, including concepts that canbe “mounted” in a “headphone” system external to the ear and remote,handheld, manually operated mechanisms.

FIGS. 28-32 illustrate an alternative embodiment for the actuationsystem for the combined PE Tube Delivery Device (PETDD). As shown inFIG. 28, the PETDD has a generally cylinder-shaped body that that canfit within the working channel of the guide block. The PETDD can includetwo actuator stages contained within the device body, one for piercingthe TM and a second one for retracting the needle and deploying the PEtube. Electrical connections to the actuator can be made to wireelements for the pierce and retract stages. Four wires can be used forthe actuator of FIG. 28 which can terminate at a flex circuit.

FIG. 29 shows a sectional view through the centerline of the PETDD ofFIG. 28. As is shown in FIG. 28, the PETDD can have a stainless steelhousing. The housing surrounds a pierce actuator spring and a retractactuator spring. The piece actuator spring is held in a compressed formby a pierce wire fuse. The retract actuator is also held in a compressedform by a retract wire fuse. The operation of the PETDD is described inconjunction with FIGS. 30-32.

The sequence depicted in FIGS. 30-32 show three stages for the device.FIG. 30 shows the insert ready state where the device is ready forinsertion of its blade. In this stage fuse wires are intact, and theactuator springs are storing mechanical energy. FIG. 31 shows the piercestate where the pierce fuse wire has vaporized, and the lancet haspierced the TM having traversed a short distance (e.g., 2 mm stroke). Asshown in FIG. 21, in this stage both the pierce and the retractactuators have traveled the same short distance (e.g., 2 mm stroke) withrespect to the outer shell. FIG. 32 shows the deploy and retract stage,where the retract/deploy fuse has vaporized. In this stage, the retractstage of the device moves back the short distance (e.g., 2 mm stroke)relative to the outer case and the pierce stage and the PE tube remainsin the TM.

Certain aspects of the embodiments of the present invention are directedtoward the unique shape of the PE tube. FIGS. 41A-C illustrate variousPE tube shapes that include interrupted medial flanges that are usefulin the automated insertion of the PE tubes via the PETDD.

In addition to the above two PETDD embodiments, a laser-based piercingtool can also be used to pierce the TM of the patient's ears. Inaddition, the PETDD may be designed such that deployment of the PE tubecommences medially to the tympanic membrane and progresses to completionlaterally to the membrane in such a manner that actuation of the deviceis accomplished from the inside out; benefits include maximizing controlof PE tube deployment such that progression is in a medial-lateraldirection (increasing safety) instead of lateral-medial (decreasingsafety).

FIGS. 42A-B illustrate a PE tube 204A that is delivered from the insideof a cutting tool. The so-called internal PE tube is configured to becompressed for delivery inside the cutting tool; a push rod can be usedto deploy the PE tube out of the cutting tool, and features of the PEtube expand to anchor it in the TM as shown in FIG. 42B. The so-calledinternal PE tube is advantageous because the cutting tool is configuredto make a controlled incision size, and the deployment of the PE tubedoes not place additional stresses on the TM, since the TM is lesslikely to be subjected to tearing, pressure or stretching of the TM asthe tube is deployed through the cutting tool. Also as shown in FIG.43A-B, the so-called internal PE tube setup can also be used with agrommet or T-tube type PE tube designs.

FIGS. 44A-B illustrate a PE tube 204C that is delivered on the outsideof a cutting tool. The so-called external PE tube can have features thathelp expand the incision in the TM. Such features include taperedleading edge flanges or thin or flexible internal flanges. The so-calledexternal PE tube can be advantageous since it will enable the formationof smaller incisions. In addition, the so-called external PE tube isless dependant on the deployable features on the PE tube, as there willbe no need for the internal compression of the PE tube during itsstorage in the PETDD device, as in the so-called internal PE tube. Inaddition, for the so-called external PE tube, the cutting tool can be aversion of a standard myringotomy spear or blade. As shown in FIG. 44A,flanges on the push rod can prevent over insertion of the PE tube. Inaddition, as shown in FIG. 44C-D, flanges on the PE tube can havecut-outs to allow for the easier passage and its deflection through theTM.

Certain aspects of the embodiments of the present invention are directedtoward the use of a cam/eccentric mechanism that is used to position thePETDD in an X-Y direction. FIGS. 37A-C illustrate an embodiment of acam/eccentric mechanism to position the PETDD in an X-Y direction. FIG.37A shows the PETDD 200 is located within the ear canal 10, and thedistal end of the PETDD is located near the TM 12. This embodiment ofthe PETDD includes a housing 260 that is configured to fit in the earcanal and/or portions of the guide block. The PETDD 200 is connected viaa cam 262 to the housing 260. The housing 260 can be affixed to theappropriate ear structure (e.g., the external ear canal). The cam 262 isconfigured to rotate within the housing 260. The PETDD 200 is mountedeccentric to the cam's centerline. In operation, when the distal (i.e.medial) end of the PETDD 200 is fixed at the guide block 100, rotationof the cam 262 allows for an approximately circular sweep of the aim ofthe PETDD in the X-Y direction with respect to the targeting on the TM12. As is shown in FIG. 37C, the cam-enabled embodiment of the PETDD isconfigured to have an aim that sweeps in a circular manner the TM 12 ina X-Y direction that is substantially parallel with the plane of the TM12. It should be realized that the back end of cam doesn't have to be inear canal. It can be located outside the ear. For example, when there isan “ear muff” type stabilization mechanism—the cam can be outside theear.

The systems and devices described above can be used to practice variousdifferent procedures in addition to the ones described above. Forexample, the guide block system can be used to provide the ability toaspirate and suction through the working channels. In addition, aclinician may also desire to use suction to gently “pull” or steer theTM back towards the guide block and/or the PETDD which would guarantee acertain distance between the actuator and the TM to allow for a saferinsertion of the PE tube.

Range Finding

In one exemplary embodiment, a light-based range finding technique canbe used. The light-based system includes two light emitting elements(such as a laser) on the PE tube placement device that produceconcentrated beams of light. The light emitting elements are oriented insuch a way that the intersection of their produced rays is at apre-determined distance from the PE tube placement device, as shown inFIG. 33. When the rays from the two light emitting elements areprojected onto a surface, such as the TM, they produce two visible dots.As the PE tube placement device moves in a direction perpendicular tothe surface of projection, the dots produced on the surface move closertogether as the designed distance (y) is approached. When the designeddistance is reached the two dots are coincident. Alternatively, thebeams could be lines that overlap to form a cross hair at the designeddistance.

An alternative technique for range finding is shown in FIGS. 34A-B,which illustrate a contact-switch-based range finding technique. Thecontact switch elements 590 displace and complete a circuit—similar to asafety switch sending voltage to a terminal. FIG. 34A shows thecontact-switch-based range finding technique that relies on a fixedretraction distance before the circuit is closed. FIG. 34B shows thecontact-switch-based range finding technique that relies on a non-fixedretraction distance before the circuit is closed. In this scheme sensorsare used to determine a contact between an in-range and an out-rangecontact positions.

The range finding embodiments described above are used to establish anX-Y target location on the TM for PE tube placement and/or amyringotomy. The range finding embodiments are also used to establish aZ distance from the TM, within a certain range, for the safety andreliability of the PE tube delivery and/or a myringotomy. The X-Y targetlocation and the Z distance are shown in FIGS. 54A-B. In addition to therange finding embodiments described above, the following range findingembodiments can also be used.

A first additional embodiment, depicted in FIGS. 55A-B, involves the useof a fine hair-like element 600 mounted on the distal end of the guideblock 100. When using this embodiment, the targeting and range findingcan be done using an endoscope 121 by observing contact and deflectionof the hair-like element 600 or whisker on the TM. In particular,targeting is achieved by observing the whisker's contact point 602 onthe TM and range finding is achieved by observing the deflection of theknown length of the whisker.

A second additional embodiment, depicted in FIGS. 56A-B, involves theuse of non-contact laser targeting. As shown in FIGS. 56A-B, two laserbeams are angled to coincide into a spot or crosshair when they are acertain distance from the TM. As shown in FIG. 56B, the beam can projecta spot shape (A). FIG. 56B also shows how the beam spot can appear onthe target surface at different ranges. When the targeting range is justright, the two beams coincide, and when the targeting distance is eithertoo close or too far, the two beams appear as two spots. Alternatively,the beams can appear as lines that can form a cross hair. For example,when the targeting range is just right, the two beams coincide to form across hair, and when the targeting distance is either too close or toofar, the two beams appear as two separated lines. One advantage of thislaser based embodiment is that it does not contact the TM and thus canbe used pre and post-anesthesia for both range finding and targeting.

A third additional embodiment, depicted in FIGS. 57A-B, involves the useof non-contact optical targeting methods. This optical and non-contacttechnique can be built into the endoscope, thus eliminating the need forseparate components. In one embodiment, the optical scheme can use afixed focal length setup. In this setup, the focal length of theendoscope 121 corresponds with the targeting range, such that when animage 604 on the endoscope screen appears focused, then targeting iswithin range. In another embodiment, the optical scheme can use areticle 606 and a dot 608. In this setup, the optical beam is projectedfrom the end of the guide block. The endoscope is configured to have areticle 606 with a circle. When the dot or beam 608 is the same size asthe circle on the reticle 606, the target is within range. When the dotor beam 608 is smaller than the circle on the reticle 606, the target istoo close and when the dot or beam 608 is larger than the circle on thereticle 606, the target is too far.

In connection with the imaging configurations, a coupler can be used toattach two endoscopes to a single camera, providing imaging from twoscopes simultaneously. Alternatively, a video splitter can be used tosend images from two cameras to a single monitor. Since the spacebetween the guide block and TM will be fluid filled, ultrasound can alsobe used for imaging. Furthermore, ultrasound can be used to drive theanesthetic across the TM and then to image the tissue region, forexample while the PE tube is placed.

In addition, range finding can also be accomplished via ultrasound,radar type technology. This can be facilitated via the insertion of amedium into space to allow the ultrasoundxz/radar methods. The mediumcan reduce energy requirement.

FIGS. 35A-B illustrate a handheld device 500 in accordance with oneembodiment of the present invention having the combined features of anotoscope, guide tube stabilizer and range finder. As is shown in FIG.35A, the device 500 includes a handle portion 502 that forms a part ofthe body of the device. The device 500 also includes a trigger 504 whichcan be used to actuate the otoscope, the laser range finder and/or theinjection of the molding or stabilizing material. The device 500 caninclude a portion that is dimensioned to receive the molding material,which in one embodiment can be a two-part silicone molding material 506.The device 500 is dimensioned to hold the guide tube 508 or the one ormore tubes described above. The distal end of the guide tube includesthe barrier material 510. The device 500 also holds optics 512 for thedirect visualization of the internal space of the ear canal. The device500 also holds laser optics 516 that are used for range or depth findingpurposes. FIG. 35B shows further details of the laser range finder 516.A laser light 530 is directed toward a splitter 531 which then directsthe split laser light to mirrors 532 which then direct the laser lighttoward a focal point 534. With the range finder 516 distance can be setwith a single laser beam through a prism 531, that splits the beam andfocuses it on the focal point 534. In operation, after the device 500has been used and removed from the ear canal, the guide tube 508 andbarrier material 510 are configured to stay behind after the moldingmaterial 506 has been delivered. The device 500 can also help maintainthe guide tube 508 or the one or more tubes in place in alignment priorto the injection of the molding material.

In addition to the above description, the following alternative conceptsare also within the conceived embodiments of the present invention. Forexample, in addition to the motor and screw drive and preloaded springembodiments described above, the drive system can be a pneumatic system,a simple solenoid-based system; or a servo solenoid-bases system. Forexample, the coupling between the drive system and the PETDD can be viaa flexible rod or a control wire. For example, the range finder can usea capacitance contact sensor or strain contact sensor. And For example,the cutting tool can be a solid blade, a hollow lance, a screw,scissors, or a laser.

As will be understood by those skilled in the art, the present inventionmay be embodied in other specific forms without departing from theessential characteristics thereof. These other embodiments are intendedto be included within the scope of the present invention, which is setforth in the following claims.

What is claimed is:
 1. A method for treating a patient, the patient having an ear canal and a target tissue including a tympanic membrane, the method comprising: introducing a fluid to the ear canal through a supply lumen extending through a fluid barrier; positioning the fluid in the ear canal, the fluid comprising a therapeutic agent; retaining the fluid with a support structure comprising the fluid barrier, the support structure supporting an electrode and a battery; coupling the support structure with an audio or video track; applying the therapeutic agent from the fluid to the target tissue by energizing the electrode with an iontophoresis potential from the battery; synchronizing the audio or video track with a noise created by a therapeutic treatment; and imaging the target tissue through the fluid barrier.
 2. A method for treating a patient, the patient having an ear canal and a target tissue including a tympanic membrane, the method comprising: introducing a fluid to the ear canal through a supply lumen extending through a fluid barrier; positioning the fluid in the ear canal, the fluid comprising a therapeutic agent; retaining the fluid with a support structure comprising the fluid barrier, the support structure supporting an electrode and a battery; coupling the support structure with an audio or video track; applying the therapeutic agent from the fluid to the target tissue by energizing the electrode with an iontophoresis potential from the battery; synchronizing the audio or video track with a noise created by a therapeutic treatment; imaging the target tissue through the fluid barrier; and perforating the tympanic membrane with reference to an image from imaging the target tissue through the fluid barrier. 